1. Field of the Invention
A quick-fastening plug and socket arrangement includes a locking sleeve arranged concentrically between the plug and the circular socket opening within which the plug is axially inserted, which locking sleeve includes a resilient projection that is radially biased outwardly into locking engagement with screw threads carried by the inner circumferential surface of the socket opening. The locking sleeve is connected against longitudinal displacement relative to an associated one of the plug and socket members, said sleeve being rotatable relative to the associated plug and socket member, thereby to release the plug for removal from the socket opening.
2. Description of Related Art
It is well known in the patented prior art to provide various plug and socket arrangements, as evidenced, for example, by the prior U.S. patents to Bury U.S. Pat. No. 7,059,891 and Schumacher et al U.S. Pat. No. 7,207,824, among others.
Many different embodiments are known for electrical plug connections of this kind. On the one hand, cables, equipped with the corresponding structural parts, can be connected with each other via such a plug connection; likewise, depending upon the design, several connections can be connected to a distributor with one plug part which distributor, in turn, is equipped with a plurality of socket counterparts to the plug parts.
The plug connections under discussion here permit a secure connection in the area of the connection points because the plug member, on the one hand, and the socket member, on the other hand, are secured via a thread-like connection with each other. In the simplest case, the plug members are equipped with a sleeve that has an outer projection that defines a so-called thread. Such designs make it necessary, after the plug contacts have been brought together, to produce a screw connection over the entire thread length. This implies by no means inconsiderable time expenditure, especially when one makes a plurality of such plug connections. Connections on distributors used in automation technology are often arranged relatively closely to each other, something that also adds to the time expenditure and makes the connection operation relatively laborious.
Therefore, plug members and corresponding socket members have been proposed which facilitate the insertion of the sleeve, on the plug side, into the socket member by simply pushing it in and, at the end of the assembly procedure, by means of a slight turn, permitting a final and axial retention between the two structural parts. But there is one disadvantage here: Designs used in the past necessitate expensive production and processing both of the sleeve of the plug part as well processing of the socket member, since currently known designs are based on the idea that [they] contain either bayonet-like connection possibilities or that both the sleeve of the plug part as well as the socket member are provided with unthreaded areas that extend in the axial direction, which facilitate an axial assembly or plugging-in, without any need for a turn and which only at the very last moment permit axial retention by turning. In the latter variant, a connection is made to an interior thread which is not provided with the axially free areas; in that case, one can furthermore not save any time when compared to the known screw connections.